Conventionally, cells have been grown attached to glass or plastic roller bottles and flasks. This approach does not lend itself to high density growth of cells or continuous cell culture, and requires large amounts of medium and space. Further, the approach is labor intensive.
To achieve higher density growth conditions, various attempts have been made to use arrangements of stacked plates, the surfaces of the stacked plates providing increased surface area for cell attachment and growth. In spite of various attempts, the cell culturing devices of the prior art all have various drawbacks, including the need for excessive amounts of medium, the inability to provide a continuous flow of nutrients to all cell-growth surfaces, the need for labor intensive monitoring and care of the growing cells and the inability to operate continuously.
One attempt to solve the problems of the prior art is disclosed in commonly assigned U.S. Pat. 5,240,854. This patent discloses a cell culture system for large scale production of cells and cell products. While this culture system solves many of the problems of the prior art, a demand exists for a similar device for small scale production. The advantage of having a cell culture system of small scale, such as the present invention, is twofold. First, the cost of a smaller system would enable smaller scale facilities to harvest cells with minimal effort and thereby save the expense of purchasing a larger scale unit. Second, a smaller unit would enable users to test and perfect procedures and growth conditions for a particular application, in the laboratory, and prior to transferring to a large scale production level system.